ApplicationException occurs when Encrypt pdf in C#

Aspose.PDF Product Family
1

Hi,
I got System.ApplicationException:You cannot change this document because it is certified. when I try to encrypt a pdf file.

Tested OSs were Win7 and Win10
.NET target platform is .net 6.0
Using SDK: Aspose.PDF for .Net 24.3

Using code:

void testEncrypt(string filename)
{
    // Open document
    Document document = new Document(filename);
    // Encrypt PDF
    document.Encrypt("user", "owner", 0, CryptoAlgorithm.RC4x128);
    // Save updated PDF
    document.Save(filename + "Encrypt_out.pdf");
}

Exception detail

System.ApplicationException
  HResult=0x80131600
  Message=You cannot change this document because it is certified.
  Source=Aspose.PDF
  StackTrace:
   在 #=z$altj3IjuYPTOtBPSUzr2p0AuT3y.#=zGS45a0g=(String #=zwH190Y8KjNOy, String #=zA8D331S0NrIV, #=z_Tj8br1bfduoZ8ywhxbyeqaW2T2b #=zxV1enwk=, CryptoAlgorithm #=zDfd2CpjWwtR_, Boolean #=zzxGA3V86P4sA)
   在 Aspose.Pdf.Document.Encrypt(String userPassword, String ownerPassword, Permissions permissions, CryptoAlgorithm cryptoAlgorithm, Boolean usePdf20)
   在 Aspose.Pdf.Document.Encrypt(String userPassword, String ownerPassword, Permissions permissions, CryptoAlgorithm cryptoAlgorithm)
   在 Program.<<Main>$>g__testEncrypt|0_3(String filename) 在 C:\.NET\ConsoleApp1\ConsoleApp1\Program.cs 中: 第 52 行
   在 Program.<Main>$(String[] args) 在 C:\.NET\ConsoleApp1\ConsoleApp1\Program.cs 中: 第 57 行

Using file:
黄石亿嘉镀铝膜 卤素 中文版(1).7z (474.3 KB)

2

@kngstr

We have opened the following new ticket(s) in our internal issue tracking system and will deliver their fixes according to the terms mentioned in Free Support Policies.

Issue ID(s): PDFNET-57057

You can obtain Paid Support Services if you need support on a priority basis, along with the direct access to our Paid Support management team.